This invention concerns the construction of retainers with embedded designs on carriers.
Retainers are widely used by orthodontic patients to maintain teeth alignment after the removal of fixed appliances.
Retainers are usually removed and cleaned periodically and may be removed at mealtimes. Some retainers are used primarily during sleep.
One of the most popular forms of retainer is a Hawley retainer, which has a labial wire having ends embedded in a plastic palatal plate. The plastic palatal plate has a central body portion made in a compound dish-like curve with a curved rearward edge and serrated lateral and frontal edges, with points which fit partially between teeth to hold the plate and the retainer in perfect alignment.
The labial wire usually extends outward from points on the edges of the plate through spaces between molars and cuspids, and arches around the cuspids and extends tightly anteriorly around the frontal teeth or incisors.
Anchor wires extend outward from the retainer body through lateral edge points which extend between molars.
The maxillary Hawley retainer used with the upper teeth has a central crowned plate which matches the curve of the hard , bony forward part of the palate or the roof of the mouth.
The tissue-side surface of the retainer body is formed in a cavity in a mold created as a positive from a negative impression taken from the patient's anatomical mouth features. The surface of the retainer which lies against the palate of the mold is left unfinished. The unfinished nature of that surface bears against the soft tissue covering the hard, bony frontal palate of the wearer and aids in the preventing of slipping. The tongue-side exposed surface of the retainer is polished smooth, because the tongue does not readily accommodate to surface irregularities.
One of the long-standing problems of retainers is that they are often made of clear or colored plastic with highly visible wires, and are made in such a shape that their configuration and appearance is unattractive so that retainers often fall into disuse. Clear or colored retainers may be difficult to see, and lost retainers are a constant and recurrent problem.
A need exists for a system to encourage the use of retainers and to help locate retainers.